[PATCH] XDMCP: For IPv6 add IPv6 link local addresses to the end of the list

[Egbert Eich]

On Sat, Feb 08, 2014 at 08:58:34PM +0600, Alexander E. Patrakov wrote:
> 
> I have looked, and I have some remarks.

Thanks for doing so!

> 
> First, there is an almost identical copy-paste between the two places where
> entries are added to linklocal_list. Maybe it's worth making that a
> function? And why the difference between IN6_IS_ADDR_LINKLOCAL in one place
> and +IN6_IS_ADDR_LINKLOCAL in the other?
> 
> Second, that piece doesn't deal with realloc failures.

Right.

> 
> Third, the commit message does not reassure the readers that XDMCP over
> link-local addresses works at all (I have not tried this) and is a
> supportable configuration. If any of these conditions are false, then let's
> just drop these addresses, like we do with IN6_IS_ADDR_LOOPBACK.

AFAIR they don't. This was why this issue had popped up.

> 
> ... OK, actually I have tested IPv6 UDP communication using link-local
> addresses using netcat6. It doesn't work (-EINVAL on bind() that is used to
> set the source address and port), so I will be very much surprised if XDMCP
> works. If that requirement did not violate the list rules, I would even
> require a tcpdump capture of a successful XDMCP session and some X11 traffic
> along with the patch.

Ok, it's been a while and I didn't write the patch but I believe the whole
reason for this patch was to move the link-local addresses out of the way
ie. at the end of the list where they don't bother anybody.
Therefore dropping them would also be an option - codewise it would be simpler
and address most of the other concerns voiced.

Reinhard, what do you thing?

Thanks for reviewing!

Cheers,
	Egbert.